Gear Advice: Long Underwear (Mid Weight)

This is also known as a base layer. The purpose is to wick away moisture from the body when active, and provide a layer of trapped warm air when not moving. You will want to pick a weight that is not so thick that you sweat a good deal when using it. By varying your layers, you can adjust this somewhat, but if your base layer is too thick, there is not much you can do about it. A mid weight or light weight layer (depending on how hot your body tends to run) is best when you are active.

Bill's Choice

Patagonia Capilene #3 (Bottoms & Long-Sleeve Zip T Top) (I would go with a #2 base if I were not doing high desert/mountain winter activities.)